Related papers: Muon Decay Spectrum: Leading Logarithmic Approxima…
Analytic formulae are given for order alpha_s perturbative QCD corrections to the double differential distribution of the tau lepton energy and the invariant mass of the tau + antineutrino system in semileptonic decays of the bottom quark.…
An expression for the Dalitz plot of the semileptonic decay of a charged kaon, including radiative corrections to order O[\alpha \pi)(q/M_1)], where q is the four-momentum transfer and M_1 is the mass of the decaying kaon, is obtained.…
I present an update on the electroweak radiative correction factor to semileptonic tau decays, including a next-to-leading order resummation of large logarithms. My result differs both qualitatively and quantitatively from the one recently…
I review recent estimates of the non-perturbative hadronic vacuum polarization contributions. Since these at present can only be evaluated in terms of experimental data of limited precision, the related uncertainties pose a serious…
Perturbative corrections of the order of $\alpha_s$ to inclusive double differential lepton distribution from $b$ quark decay are considered. A perturbative correction to the charged lepton energy spectrum has been calculated for an…
Hadronic decays of the $\tau$ lepton provide a clean environment to study hadron dynamics in an energy regime dominated by resonances. The interesting information is captured in the spectral functions. Recent results from ALEPH on exclusive…
An analytical approach is applied to the calculation of some dimensionally-regulated two-loop vertex diagrams with essential on-shell singularities. Such diagrams are important for the evaluation of QED corrections to the muon decay, QCD…
We revisit the total decay rate of a muon being in the ground state of a Coulomb potential with atomic charge numbers $4\leq Z \leq 9$. The discrepancy between the perturbative $(\alpha Z)^2$ result of [Phys. Rev. \textbf{119}, 365 (1960)]…
We consider massive Dirac electron antineutrino to be observed in the muon decay, $\mu^{-} \rightarrow e^- +\bar{\nu}_{e} + \nu_{\mu}$, at rest in the LAB reference frame. A computation of $\bar{\nu}_{e}$ differential direct spectral shape…
The QED contribution to the anomalous magnetic moments of electron and muon are known very precisely up to the order $\alpha^4$. However, the knowledge of $\alpha^5$ term will also be required when the precision of measurement improves…
Power-suppressed corrections to parton evolution may affect the theoretical accuracy of current determinations of parton distributions. We study the role of multigluon-exchange terms in the extraction of the gluon distribution for the Large…
Of the the three best-measured electroweak observables, $\alpha$, $G_\mu$ and $M_Z$, the first two are extracted from low-energy processes. Both $G_\mu$ and $M_Z$ are now known to an accuracy of about 2 parts in $10^5$ and there is a…
We show how radiative QCD corrections calculated in terms of quarks can be incorporated at the hadron level in inclusive semileptonic B-meson decays. The bound state effects are described by a momentum distribution function of the $b$…
We present an estimate of perturbative QCD corrections to the decay $Z \to Wu\bar d$. A simple approximate approach is described in detail. The difference of masses of $M_Z$ and $M_W$ is used as an expansion parameter. A complete analytical…
By using the non-relativistic effective Lagrangian approach to bound states, a complete expression for the isospin-breaking corrections to the energy levels and the decay widths of kaonic hydrogen is obtained up-to-and-including…
We extend our relativistic quark model to the study of the decay Lambda_b -> Lambda_c ell nu and verify that the model satisfies the heavy-quark symmetry constraints at order 1/mQ^2. We isolate a strong dependence on a parameter which…
A search for the lepton-flavor violating $\mu^{+}\rightarrow e^{+}\gamma$ decay using polarized muons is proposed. By measuring the angular distribution of $e^{+}$s with respect to the muon spin direction, in particular antiparallel…
The present knowledge of Lamb shift, fine- and hyperfine structure of the $\mathrm{2S}$ and $\mathrm{2P}$ states in muonic deuterium is reviewed in anticipation of the results of a first measurement of several $\mathrm{2S-2P}$ transition…
Radiative corrections to the decay rate in the low-Z hydrogen-like muonic atoms are considered. The correction arises from the Uehling potential and it has the relative order of alpha. The numerical results are reported for the 2p-1s…
A comprehensive overview of kaon decays is presented. The Standard Model predictions are discussed in detail, covering both the underlying short-distance electroweak dynamics and the important interplay of QCD at long distances. Chiral…